Preparation of a solid flavour composition, a composition, food comprising the composition and a flavour imparting method

ABSTRACT

A process of forming a reaction flavour solid composition, the process comprises the step of heating an aqueous slurry containing reaction flavour precursor compounds to form a reaction flavour, and concomitantly drying the slurry using microwave radiation to form a reaction flavour solid composition.

FIELD

This invention relates to a method of forming reaction flavour solidcompositions by means of microwave radiation; reaction flavour solidcompositions made according to said method; and to foods or beveragescontaining said reaction flavour solid compositions.

BACKGROUND

Generating flavour and/or colour in foods by means of microwave cookingis known in the art, see for example EP 2 797 427, U.S. Pat. No.4,940,592 or U.S. Pat. No. 5,053,236. Microwaves have also been used fordrying, see e.g. CN 101263888 or CN 101283775. However, theextemporaneous generation of flavour and/or colour as a result ofcooking food is distinct from the industrial production reactionflavours, which is essentially a process of preparing flavourcompositions external of a food or beverage matrix.

A “reaction flavour” is an art recognised term that describes a flavourcomposition that can be used to impart, modify or improve the flavour ofall manner of foods or beverages. They are formed by reacting reactionflavour precursor ingredients under controlled reaction conditions. Areaction flavour is not a food as such; it is an article of manufacturethat is intended to be added to foods or beverages to impart flavourthereto, or to modify or improve flavour in a food or beverage. Reactionflavours are essentially non-nutritional, that is, their substantialpurpose is to impart flavour to foods or beverages, or to enhance,modify or improve the flavour of food or beverages to which they areadded, not to provide nutrition. Reaction flavour solid compositions arereaction flavours in the form of a solid, for example a powdered solidor paste.

Reaction flavour precursor ingredients employed in the preparation ofreaction flavour solid compositions may have little or no flavour in andof themselves, this being developed or produced by a complex series ofconsecutive and/or competing reactions, such as Maillard reactions,Schiff base formation, Strecker degradation, caramelization reactions,and/or other reactions that are beneficial in the development of flavourand/or colour, all of which are well known to the person skilled in theart. Permitted precursor ingredients and recommended reaction conditionsare set out in guidelines provided by regulatory authorities known tothe person skilled in the art.

The use of a microwave for Maillard reactions has been described in e.g.CN 104397661, CN 101756148, CN 102283365 or CN 103564395.

A reaction flavour typically consists of a complex multi-component blendof both volatile and non-volatile reaction products, as well as anyunreacted starting materials. In the production of a reaction flavour,its compositional make-up can be sensitive to reaction parameters andmay vary in terms of its component parts, or in the pattern ofdistribution of those component parts. Important reaction parameters caninclude precursor ingredient chemistry, reaction time and temperature,moisture, pressure, pH, and the like. If one or more of these parametersis not controlled, the flavour profile and/or colouration of thereaction flavour can be adversely affected, for example by failure toconvert all of the starting materials, or by the development ofoff-tastes.

In the industrial production of reaction flavours, the skilled personmust not only take into account the foregoing reaction parameters orvariables, it must also take into account process engineeringconsiderations. For example, viscosity control in reaction media is animportant process parameter, which on an industrial scale will impactoperations such as pumping, stirring, blending and filtering, and tofacilitate these operations, it is conventional to form reactionflavours in reaction media consisting of highly dilute aqueous slurries.Furthermore, in addition to controlling viscosity in this way, employinghigh levels of water can help control heat transfer and preventover-heating or localized heating during reaction flavour formation.

The use of highly dilute slurries does have some disadvantages, however.Reaction flavours are usually presented commercially in the form ofsolid compositions. Reaction flavours in dry form are particularlyimportant for reason of their physical and microbiological stability, aswell as for supply chain considerations, such as ease of storage,handling, dosing, and the like. Removal of water from the reactionmixture once a reaction flavour is formed is therefore a criticalprocess step.

Using conventional process conditions, after cooking a slurry to createa reaction flavour in a first step, the slurry is dehydrated in a secondstep by spray drying or vacuum oven drying. Spray drying is relativelyinexpensive, but this technique does require the use of relative largeamounts of carrier material, which can be detrimental to the flavourprofile and mouth feel of a finished reaction flavour. More commonly, inthe second step, dehydration is accomplished using vacuum oven drying.In this case, after preparing the reaction flavour, the slurry istransferred to drying trays and the trays are inserted into a vacuumoven, whereupon the water is evaporated by heating (usually below 100°C.) under reduced pressure. However, the time and energy required todehydrate slurries in this way is rather wasteful of resources. Theprocess is laborious, complex and expensive; and the dependency on longdrying times and elevated temperatures means that without carefulin-process control, the drying process can leave its imprint on theflavour quality and authenticity of reaction flavour solid compositions.

Nevertheless, reaction flavour solid compositions are easy to handle andhave many uses as additives in foods or beverages, and are much desiredby flavour manufacturers and food and beverage manufactures alike. Thereremains a need to provide an industrial method of forming reactionflavour solid compositions in a cost effective and efficient manner,which can deliver reaction flavour solid compositions exhibitingintense, authentic flavour profiles that are characteristic of, orimprove upon, reaction flavour solid compositions formed by conventionalprocesses.

SUMMARY OF THE INVENTION

In addressing the deficiencies in the prior art, the applicantdiscovered in a surprising manner that reaction flavours can be bothformed and dehydrated in a single heating step using microwaveradiation. The applicant is neither aware of any prior art process offorming reaction flavours in an aqueous slurry, whilst concomitantlydehydrating the slurry to form reaction flavour solid compositions, norspecifically, such a process carried out using microwave radiation.

The present invention provides in a first aspect a process of preparinga reaction flavour solid composition comprising the step of heating anaqueous slurry containing reaction flavour precursor compounds usingmicrowave radiation.

In another aspect the invention provides a reaction flavour solidcomposition obtainable by a process comprising the step of heating anaqueous slurry containing reaction flavour precursor compounds usingmicrowave radiation.

In another aspect the invention provides a food or beverage comprising areaction flavour solid composition of the invention.

In yet another aspect the invention provides a method of impartingflavour to a food or beverage, or modifying or improving the flavour ofa food or beverage, said method comprising the step of adding to saidfood or beverage a reaction flavour solid composition defined herein.

These and other aspects and embodiments of the invention will be furtherunderstood with reference to the following description and examples.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is based on the surprising discovery that anaqueous slurry comprising reaction flavour precursor compounds can beconverted to a reaction flavour and concomitantly dehydrated by meansheating the slurry using microwave radiation. Thus, in contrast to theprior art, reacting and drying are performed in one and the same step.Microwave radiation provides the heat source to both form a reactionflavour in the slurry and to dehydrate the slurry, thereby to provide areaction flavour solid composition.

The term “reaction flavour”, as used throughout this disclosure, refersto a flavour composition that can be used to impart, modify or improvethe flavour of all manner of foods or beverages. It is typically formedby reacting reaction flavour precursor ingredients under controlledreaction conditions. A “reaction flavour” is not a food as such; it isan article of manufacture that is intended to be added to foods orbeverages to impart flavour thereto, or to modify or improve flavour ina food or beverage. The term “reaction flavour” is meant to encompassboth “process flavours” and “flavouring preparations”.

According to the EFFA Guidance Document on the EC Regulation onFlavourings, “thermal process flavours” are reaction flavours that areformed from reducing sugar and amino acids/amine sources. “Flavouringpreparations”, on the other hand, are handled as outlined in the “EFFAGuidance Document for the Production of Natural Flavouring Substances &(Natural) Flavouring Preparations in the EU.

The discovery that microwave radiation can be employed to form areaction flavour in a slurry and to concomitantly dehydrate the slurryto form a reaction flavour solid composition, permits of much fasterprocessing times than were heretofore possible using prior art processesof sequentially heating an aqueous slurry to form the reaction flavourin a first step, and thereafter carrying out a separate drying step in aconventional vacuum drying oven, or by spray drying.

Furthermore, by means of the present invention, it is possible to formreaction flavour solid compositions, which are highly reminiscent ofreaction flavour solid compositions formed by conventional processes,but in much shorter periods of time. Still further, because thesynthesis of the reaction flavour and drying of the slurry are carriedout concomitantly, the chemistry of reaction flavour synthesis proceedsin a relatively low water content environment, enabling the formation ofa variety and/or abundance of reaction flavour components, whichhitherto could not be achieved using conventional processes.

In a conventional process, because a reaction flavour is formed in highwater content reaction medium, and it is not desired to dehydrate thereaction medium, the temperature does not rise above 100° C., orpossibly slightly higher (e.g. about 120° C.) if the reaction medium isunder pressure because of the reaction being carried out in a closedvessel. By contrast, in accordance with the present invention,relatively low water content slurries can be employed initially, and thewater content is reduced further due to dehydration. This results inshorter processing times and higher processing temperatures during thedevelopment of the reaction flavours. As a result of higher reactiontemperature and lower reaction times, it is possible to create reactionflavours that offer completely new and interesting flavour profiles.

Indeed, the applicant has found it is possible to create reactionflavour solid compositions comprising an abundance and/or variety ofimportant reaction flavour components, which is not achievable withconventional processes.

More particularly, the invention provides reaction flavour solidcompositions comprising a surprising abundance and/or variety ofreaction flavour components selected from ketopiperazines, piperazines,pyrrolizines, pyrazines, sulphides, thiols and maltol derivatives, andmixtures thereof. These reaction flavour components are particularlyuseful ingredients in all manner of reactions flavour solidcompositions, but particularly those intended to deliver or contributeto savoury, poultry, roasted, crusty bread, toasted cheese, seared oranimalic flavour notes.

The discovery that desirable reaction flavours can be formed anddehydrated with relatively short processing times and at relativelyhigher temperatures is indeed very surprising and counter-intuitivegiven that those skilled in the art of manufacturing reaction flavourswould understand and accept that flavour and colour development dependsupon adherence to established reaction variables discussed above,including time and temperature, and that the industry-standard cookingand drying steps (such as vacuum drying or spray drying) are critical inorder to create desired flavour profiles of reaction flavour solidcompositions.

In an embodiment of the present invention, the method of forming areaction flavour solid composition, comprises the step of providing anaqueous slurry of reaction flavour precursor compounds containing waterin amounts up to 50 wt %, in particular 10 to 50 wt %, more particularly10 to 30 wt %, more particularly 15 to 30 wt %, and more particularlystill 10 to 20 wt %, and applying microwave radiation thereto for aperiod of time sufficient to dehydrate the slurry and produce a reactionflavour solid composition.

After dehydration of the slurry, the resulting reaction flavour solidcomposition can have a water content of 0.1 to 5.0 wt %, moreparticularly 0.5-5.0 wt %, more particularly 1.0 to 4.0 wt %, moreparticularly 1.0 to 3.0 wt %, and more particularly still 1.0 to 2.0 wt%.

In accordance with the invention, microwave radiation is applied to anaqueous slurry, causing precursor compounds contained therein to reactand form reaction flavours. Concomitantly, the heat generated by themicrowave radiation dehydrates the slurry.

The temperature of the slurry is such as to cause the reaction flavourto form in a time scale during which the slurry also dehydrates to formthe reaction flavour solid composition.

In an embodiment of the invention, the slurry may be heated to atemperature of 125° C., provided that the temperature of the slurryshould not be at 125° C. for a period exceeding 12 hours.

In an embodiment of the present invention, the slurry may be heated to atemperature of 140° C. provided that the temperature of the slurryshould not be at 140° C. for a period exceeding 4 hours.

In an embodiment of the present invention, the slurry may be heated to atemperature of 150° C. provided that the temperature of the slurryshould not be at 150° C. for a period exceeding 2 hours.

In an embodiment of the present invention, the slurry may be heated to atemperature of 160° C. provided that the temperature of the slurryshould not be at 160° C. for a period exceeding 1 hour.

In an embodiment of the present invention, the slurry may be heated to atemperature of 180° C. provided that the temperature of the slurryshould not be at 180° C. for a period exceeding 15 minutes.

Depending on how the slurry is heated, its temperature can be controlledin order to mimic different types of cooking techniques, such asboiling, grilling, or roasting. The temperature should be controlled toensure the desired flavour profile is created. Time is another importantfactor in the processing of slurries. If a slurry is not heated for aadequate time period, off-notes associated with unreacted precursorcompounds, or over-roasted or even burnt notes can develop that canoverpower other desired, more subtle notes.

Any reaction flavour can be generated by the methods of the presentinvention. Some of the most common reaction flavours include those thatprovide or contribute to red meat notes, poultry notes, vegetable notes,bread crust notes, chocolate notes, caramel notes, popcorn notes andfire roasted notes.

A particular feature of the present invention is that both the synthesisof the reaction flavour and its dehydration to form a reaction flavoursolid composition occur essentially simultaneously in a single stepprocess. It was entirely surprising that a process flavour could beformed, and not over-cooked, within the same time frame as the slurry isdehydrated to form the solid composition. However, the applicant foundthat this could be achieved by means of appropriate control of processvariables.

In an embodiment of the invention, the slurry is heated for a period oftime ranging from 1 to 15 minutes, more particularly 1 to 10 minutes,more particularly still from 1 to 7 minutes, and still more particularly1 to 5 minutes. The temperature of the slurry during the period ofheating may be up to 180° C.

In a more particular embodiment, the slurry may be heated to 100° C. fora period of time to drive off most of the water by evaporation. Theperiod of time will depend upon the water content of the slurry, buttypically can range from about 1 to about 5 minutes.

Thereafter, the temperature of the slurry may be increased to 130, 140,150 160 or 180° C. for a period of time both to complete formation ofthe reaction flavour, as well as to drive off any remaining water tocomplete the dehydration. A suitable time period may be as little as 10seconds, up to 1 minute, up to 2 minutes, up to 3 minutes, up to 4minutes, or up to 5 minutes.

The reaction flavour solid composition can be cooled by switching offthe microwave power supply, or by removing it from the microwave oven.

Heating of the slurry may be undertaken at ambient pressure, or undervacuum. A vacuum of 100 mbar to 1 mbar is suitable in the exercise ofthe present invention.

In an embodiment of the invention, microwave radiation is applied to theslurry that is in the form of a film. The film may be formed by casting,pouring or pumping the slurry onto an evaporation surface.

The thickness of the film is selected having regard for considerationsthat the slurry must be dehydrated within a period of time in which thedesired reaction flavour is developed. It is also necessary for theincident microwave radiation to penetrate the film to ensure efficientand even heating. The surface temperature of the film can be measuredusing standard infra-red sensors placed at intervals along the length ofthe evaporation surface.

Suitable film thicknesses fall within the range of about 0.1 to about5.0 cm, more particularly 0.3 to 5.0 cm, more particularly 1.0 to 4.0cm, and more particularly still 1.0 to 3.0 cm.

A typical apparatus for evaporating water from a film of slurry maycomprise an evaporation surface upon which a film of the aqueous slurrymay be cast, poured or pumped. The surface may consist of a tray, uponwhich the slurry is cast before the tray and slurry are placed into amicrowave oven. Alternatively, the surface may be a belt upon which theslurry is cast, which can be fed through a microwave oven disposed inthe path of the belt, and through which the belt moves, thereby to heatthe slurry for the time and at a temperature referred to hereinabove.

After passing through the microwave oven, the resultant reaction flavoursolid composition may be presented in the form of a viscous paste, cake,ribbon, or the like.

At this stage, the reaction flavour solid composition may be subjectedto further processing steps. For example, a reaction flavour solidcomposition in the form of a viscous paste may be subjected to a processof extrusion or moulding if it is desired to shape it, package it, orthe like.

A reaction flavour solid composition in cake or ribbon form may bemilled, ground and graded by sieving to render it in the form of apowder, granule or the like, having a desired particle size.

The viscosity of the aqueous slurry should be such as to be easily castor pumped onto the evaporator surface, and be sufficiently immobile onthe surface during processing.

A suitable viscosity would fall within the range of about 150 to 200,000centipoise at room temperature, preferably 1′000 to 50′000 centipoise.

Any industrial microwave ovens may be employed in a method according tothe present invention. Suitable microwave ovens include a 30 kW /915 MHz(50 kVA) up to 100 kW/915 MHz (150 kVA); or a 100 W/2450 MHz (0.15 kVA)up to 30 kW/2450 MHz (45 kVA).

Microwave energy input into the slurry—typically an aqueous slurry—maybe typically in the range of 3-100 kW, or even higher, preferably 30-100kW.

Aside from the water content of the slurry, which as stated above can beup to 50 wt %, the remaining mass of the slurry is comprised of reactionflavour precursor compounds, and any processing aids deemed necessary,such as proteins, or fragments of proteins, carbohydrates, fats andsalts, and carriers.

Whereas fats and salts may be added to the slurry for the purpose ofgenerating flavour, they may also aid in processing. For example, fatsor oils ensure good heat dissipation throughout the slurry. The additionof salts can promote energy uptake into the slurry and increase thespeed of heating.

Carriers may also be incorporated into the slurry. Carriers includefibrous materials and maltodextrins. They can help to ensure that theprocess flavour solid composition is obtained as dry powder, which inturn will facilitate any down-stream processing steps, such as millingand the like.

Precursor compounds that may be employed in the slurry are well known inthe art, and they may vary, in a manner known to a skilled flavourist,depending upon the particular reaction flavour that it is desired tocreate. Precursor compounds include amino acids/amine sources (or theirsources) and reducing sugars. The slurries may also include lipids orfats, spices and protein sources, such as hydrolyzed vegetable proteins(HVPs) or yeast autolysates.

In addition to these materials, the slurry may contain other materialsthat can modify taste or flavour, including sulphur sources, meatpowders, powdered broths or stocks, and a fuller discussion of suchingredients is set forth hereinbelow.

Amino acid/amine sources may be selected from the group consisting ofcysteine, methionine, alanine, glycine, lysine, arginine, histidine,tryptophan, proline, valine, glutamic acid, glutamine, aspartic acid,glutathione, other sulphur-containing peptides, HVP (groundnut, soybeanwheat/maize gluten), other hydrolysed proteins (for example those thatcan be derived from milk, egg, fish, blood, liver, bone, collagen),yeast extract, autolysed yeast, meat extract, taurine and pyrrolidonecarboxylic acid.

Reducing sugars are those that either have an aldehyde group or arecapable of forming one in solution through isomerism. The aldehyde groupallows the sugar to act as a reducing agent in the Maillard reaction,important in the browning of many foods. Cyclic hemiacetal forms ofaldoses can open to reveal an aldehyde and certain ketoses can undergotautomerization to become aldoses. Examples of reducing sugars include:glucose, fructose, xylose, glyceraldehyde, galactose, lactose,arabinose, maltose, glucose polymers such as starch, hydrolyzed starch,and starch-derivatives like glucose syrup, maltodextrin, and dextrin.

Sulphur sources may be selected from the group consisting of hydrogensulphide, cysteine, cystine, methionine, glutathione, thaimin, inorganicsulphides, organic thiols and sulphides, 2-mercaptoethanol derivatives,e.g. mercaptoacetaldehyde and/or its dimer 2,5-dihydroxy-1,4-dithiane,5-hydroxy-3-mercaptopentanone, 3-mercaptopropan-1-ol, 4,5-substitutedthiazoles, thiocarbonates, thioamides, 2-mercaptoalkoanoic acids/amides,mercaptoalkylamines, aminosulphides, S-acetylmercaptosuccinic acid,vegetable extracts, fermented vegetable juices, yeast extract, autolysedyeast, egg protein and meat extract.

The ratio between an amino acid and a reducing sugar can vary withinwide limits, for example a typical ratio of amino acid to carbohydrateis 1:5 but this can deviate significantly, depending upon the effectthat is desired to be achieved.

In an embodiment of the invention a reaction flavour solid compositionwill be the product of a slurry containing up to 30 wt % water; up to 70wt % of protein; up to 6 wt % of reducing carbohydrate, such as reducingsugars; up to 4 wt % lipids; up to 20 wt % carrier.

In another embodiment of the invention a reaction flavour solidcomposition will be the product of a slurry containing up to 30 wt %water; up to 30 wt % salts; up to 35 wt % reducing carbohydrates, suchas reducing sugars; up to 15 wt % lipids; up to 20 wt % amino acids; andup to 14 wt % carrier.

The pH of the slurry can be adjusted in the range of 0.5 to 8, moreparticularly 2 to 8, and more particularly still 4 to 8. Any food gradeacids and bases can be used. Examples of the acids include lactic acid,phosphoric acid, acetic acid, citric acid, malic acid, tartaric acid,oxalic acid, tannic acid, caffeotannic acid, benzoic acid, butyric acid,and combinations thereof. Examples of bases include sodium hydroxide,sodium carbonate, potassium bicarbonate, and sodium acetate.

The reaction flavour solid compositions of the present invention mayrepresent a complete flavour composition that may be blended with a foodor beverage to impart flavour thereto, or modify or improve the flavourthereof. Alternatively, the reaction flavour solid composition may formonly a part of a complete flavour composition, and the reaction flavoursolid composition can be mixed with other flavour ingredients to formthe complete flavour composition.

A skilled flavourist will be able to mix a reaction flavour solidcomposition of the present invention with other known ingredientsemployed in flavour compositions to develop a wide variety of completeflavour compositions to satisfy the requirements of the food andbeverage industry.

Those other known ingredients useful in complete flavour compositionsmay be added to the slurry before the formation of the reaction flavoursolid composition, or they may be blended with a reaction flavour solidcomposition after it is formed, or both.

A complete flavour composition may comprise a reaction flavour solidcomposition as described herein; aroma volatiles and other flavouringredients generally known in the art; and other synergists orenhancers, such as fats or fatty acids, or their sources, herbs, spicesand the like; pH regulators; inorganic salts; taste masking agents,taste sensates; vitamins; dyes; colourants; pigments, and the like.

Other ingredients include aldehyde and ketone sources, includingacetaldehyde, propanal, butanal, methylpropanal, C3 to C5 alkanals, HVP,alpha diketones and sources thereof, including butanedione,pentane-2,3-dione, pyruvaldehyde, pyruvic acid, glyceraldehyde, glyoxal,dihydroxyacetone, alpha-ketobutyric acid,heptane-3,4-dione-2,5-diacetate, HMFone, HDFone, and relatedderivatives, ascorbic acid, 5-ketogluconic acid, cyclotene, maltol,lactic acid, glycolic acid, malic acid, tartaric acid, and proteinhydrolysates.

Examples of flavour enhancers and their sources include MSG, IMP, GMP,yeast extract, autolysed yeast, HVP,2-furfuryl-thioinosine-5′-phsophate, 2-allyloxyinosine-5′-phosphate,2-(lower alkoxy) inosine-5′-phosphate, 2-benzylthioinosine-5′-phosphate,4-glucosylgluconic acid, and cyclotene.

Examples of pH regulators include mono-di- and tri-basic inorganicacids, such as HCl, sulphuric acid and phosphoric acid, organic acids,including succinic, citric, lactic, malic, tartaric, acetic andpropanoic; amino acids, including valine, glycine and glutamic acids.

Examples of fats include fats of beef, chicken, coconut, othertriglycerides, fatty acids, and their esters.

Examples of inorganic salts include chlorides and phosphates.

Depending upon the flavour profile that a skilled flavourist is tryingto achieve, a complete flavour composition might additionally containone or more of the following ingredients:

acetaldehyde (apple), dimethyl sulfide, ethyl acetate, ethyl propionate,methyl butyrate, and ethyl butyrate; flavour oils containing volatilealdehydes or esters include, e.g., cinnamyl acetate, cinnamaldehyde,citral, diethylacetal, dihydrocarvyl acetate, eugenyl formate, andp-methylanisole. Further examples of volatile compounds that may bepresent in the flavour oils include:

benzaldehyde (cherry, almond); cinnamic aldehyde (cinnamon); citral,i.e., alpha citral (lemon, lime); neral, i.e., beta-citral (lemon,lime); decanal (orange, lemon); ethyl vanillin (vanilla, cream);heliotropine, i.e., piperonal (vanilla, cream); vanillin (vanilla,cream); alpha-amyl cinnamaldehyde (spicy fruity flavours); butyraldehyde(butter, cheese); valeraldehyde (butter, cheese); citronellal (modifies,many types); decanal (citrus fruits); aldehyde C-8 (citrus fruits);aldehyde C-9 (citrus fruits); aldehyde C-12 (citrus fruits); 2-ethylbutyraldehyde (berry fruits); hexenal, i.e., trans-2 (berry fruits);tolyl aldehyde (cherry, almond); veratraldehyde (vanilla);2,6-dimethyl-5-heptenal, i.e., melonal (melon); 2-6-dimethyloctanal(green fruit); and 2-dodecenal (citrus, mandarin); cherry; or grape andmixtures thereof;

spice oleoresins derived from allspice, basil, capsicum, cinnamon,cloves, cumin, dill, garlic, marjoram, nutmeg, paprika, black pepper,rosemary, and turmeric, essential oils, anise oil, caraway oil, cloveoil, eucalyptus oil, fennel oil, garlic oil, ginger oil, peppermint oil,onion oil, pepper oil, rosemary oil, spearmint oil, citrus oil, orangeoil, lemon oil, bitter orange oil, tangerine oil, alliaceous flavours,garlic, leek, chive, and onion, botanical extracts, arnica flowerextract, chamomile flower extract, hops extract, marigold extract,botanical flavour extracts, blackberry, chicory root, cocoa, coffee,kola, liquorice root, rose hips, sarsaparilla root, sassafras bark,tamarind and vanilla extracts, protein hydrolysates, hydrolyzedvegetable proteins, meat protein hydrolyzes, milk protein hydrolyzatesand compounded flavours both natural and artificial including thosedisclosed in S. Heath, Source Book of Flavors, Avi Publishing Co.,Westport Conn., 1981, pages 149-277;

valerian oil; 3,4-dimeth-oxyphenol; amyl acetate; amyl cinnamate,γ-butyryl lactone; furfural; trimethyl pyrazine; phenyl acetic acid;isovaleraldehyde; ethyl maltol; ethyl vanillin; ethyl valerate; ethylbutyrate; cocoa extract; coffee extract; peppermint oil; spearmint oil;clove oil; anethol; cardamom oil; wintergreen oil; cinnamic aldehyde;ethyl-2-methyl valerate; γ-hexenyl lactone; 2,4-decadienal;2,4-heptadienal; methyl thiazole alcohol (4-methyl-5-β-hydroxyethylthiazole); 2-methyl butanethiol; 4-mercapto-2-butanone;3-mercapto-2-pentanone; 1-mercapto-2-propane; benzaldehyde; furfural;furfuryl alcohol; 2-mercapto propionic acid; alkyl pyrazine; methylpyrazine; 2-ethyl-3-methyl pyrazine; tetramethyl pyrazine; polysulfides;dipropyl disulfide; methyl benzyl disulfide; alkyl thiophene;2,3-dimethyl thiophene; 5-methyl furfural; acetyl furan; 2,4-decadienal;guiacol; phenyl acetaldehyde; β-decalactone; D-limonene; acetoin; amylacetate; maltol; ethyl butyrate; levulinic acid; piperonal; ethylacetate; n-octanal; n-pentanal; n-hexanal; diacetyl; monosodiumglutamate; monopotassium glutamate; sulfur-containing amino acids, e.g.,cysteine; hydrolyzed vegetable protein; 2-methylfuran-3-thiol;2-methyldihydrofuran-3-thiol; 2,5-dimethylfuran-3-thiol; hydrolyzed fishprotein; tetramethyl pyrazine; propylpropenyl disulfide; propylpropenyltrisulfide; diallyl disulfide; diallyl trisulfide; dipropenyl disulfide;dipropenyl trisulfide; 4-methyl-2-[(methylthio)-ethyl]-1,3-dithiolane;4,5-dimethyl-2-(methylthiomethyl)-1,3-dithiolane; and4-methyl-2-(methylthiomethyl)-1,3-dithiolane.

Complete flavour compositions may contain taste masking agents. Tastemasking agents are substances for masking one or more unpleasant tastesensations, in particular a bitter, astringent and/or metallic tastesensation or aftertaste, which substances can be a constituent of theproducts according to the invention. Examples include dihydrochalcones,nucleotides, sodium salts, hydroxyflavanones and the like.

Complete flavour compositions may contain taste sensates. Taste sensatesinclude hot tasting, salivation-inducing substances, substances causinga warm or tingling feeling, and cooling active ingredients.

Examples of hot tasting and/or salivation-inducing substances and/orsubstances which cause a feeling of warmth and/or a tingling feeling onthe skin or on the mucous membranes are: capsaicin, dihydrocapsaicin,gingerol, paradol, shogaol, piperine, carboxylic acid-N-vanillylamides,in particular nonanoic acid-N-vanillylamide, pellitorin or spilanthol,2-nonanoic acid amides, in particular 2-nonanoic acid-N-isobutylamide,2-nonanoic acid-N-4-hydroxy-3-methoxyphenylamide, alkyl ethers of4-hydroxy-3-methoxybenzyl alcohol, in particular4-hydroxy-3-methoxybenzyl-n-butylether, alkyl ethers of4-acyloxy-3-methoxybenzyl alcohol, in particular4-acetyloxy-3-methoxybenzyl-n-butylether and4-acetyloxy-3-methoxybenzyl-n-hexylether, alkyl ethers of3-hydroxy-4-methoxybenzyl alcohol, alkyl ethers of 3,4-dimethoxybenzylalcohol, alkyl ethers of 3-ethoxy-4-hydroxybenzyl alcohol, alkyl ethersof 3,4-methylene dioxybenzyl alcohol, (4-hydroxy-3-methoxyphenyl)aceticacid amides, in particular (4-hydroxy-3-methoxyphenyl)aceticacid-N-n-octylamide, vanillomandelic acid alkylamides, ferulicacid-phenethylamides, nicotinaldehyde, methylnicotinate,propylnicotinate, 2-butoxyethylnicotinate, benzylnicotinate,1-acetoxychavicol, polygodial and isodrimeninol.

Hot tasting natural extracts and/or natural extracts which cause afeeling of warmth and/or a tingling feeling on the skin or on the mucousmembranes and which can be a constituent of a complete flavourcomposition are: extracts of paprika, extracts of pepper (for examplecapsicum extract), extracts of chili pepper, extracts of ginger roots,extracts of Aframomum melgueta, extracts of Spilanthes-acmella, extractsof Kaempferia galangal or extracts of Alpinia galangal.

As stated hereinabove, any one or a combination of these ingredients maybe added to the slurry during reaction flavour formation, or they may beblended with the reaction flavour solid composition, once the latter isformed in accordance with a method according to the invention.

In addition to the aforementioned ingredients, a complete flavourcomposition may contain carrier materials. Carrier materials areemployed, particularly when the reaction complete flavour composition ispresented in the form of a powder, as flow aids, or extenders, or toprovide physical stability to the powder by modifying the glasstransition temperature (Tg) of the powder.

Suitable carriers which may be included as a component of the reactionflavour solid composition as such, or as a component in a completeflavour compositions include but are not limited to sugars, sugarderivatives, modified starches, proteins, alcohols, celluloses,dextrins, gums, sugar polyols, peptides, acids, carbohydrates,hydrocolloids. Particular examples of suitable materials include sugarssuch as gum arabic, capsul, maltose, sucrose, glucose, lactose,levulose, trehalose, fructose, ribose, dextrose, isomalt, sorbitol,mannitol, xylitol, lactitol, maltitol, pentatol, arabinose, pentose,xylose, galactose; hydrogenated starch hydrolysates, inulin,oligosaccharides such as oligo fructose; maltodextrins or dextrins(i.e., soluble fiber); modified starch; sugar fruit gran; corn syrupsolids; sugar white gran; hydrocolloids such as agar, gum acacia,modified gum acacia, sodium alginate, potassium alginate, ammoniumalginate, calcium alginate or carrageenan; gums; polydextrose;celluloses such as sodium carboxymethylcellulose, enzymaticallyhydrolyzed carboxy methyl cellulose, methyl cellulose, hydroxypropylcellulose and hydroxypropyl methyl cellulose; proteins such as gelatine,pea protein, soy and whey protein isolates and hydrolyzates, and sodiumcasemates; silicon dioxide; and derivatives and mixtures thereof.

Carriers may be employed in complete flavour compositions in amounts of5 to 25 wt % based on the dry weight of the reaction flavour solidcomposition.

Within the scope of this invention are foods or beverages containing areaction flavour solid composition of this invention, alone or as a partof a complete flavour composition.

A feature of the present invention is that the reaction flavour solidcomposition is a product that is formed externally of a food or beveragematrix. It is an article of manufacture that can impart to, or modify orimprove the flavour of a food or beverage, either alone or as part of acomplete flavour composition, by virtue of it being mixed with orapplied to a food or a beverage. The reaction flavour solid compositionis not formed in or on a food or beverage matrix whilst the food orbeverage is in the process of being heated or cooked

Although the amount of a particular reaction flavour solid compositionemployed in a food or beverage will be dependent upon the intendedapplication and effect that is desired to be achieved, generally, anamount of 0.1 to 1% by weight and preferably, about 0.1 to 0.5% byweight is appropriate to impart a desirable flavour and/or aroma to afood or beverage, or modify or improve the flavour and/or aroma of afood or beverage.

Examples of foods or beverages include baked products, snack foods,cereal products, alcoholic and non-alcoholic beverages, spice blends,ready-to-heat foods, ready-to-eat meals, dairy products, meat products,seasoning preparations, ketchup, sauces, dried vegetables, soups,bouillon, noodles, frozen entrees, gravy, and desserts.

Reaction flavour solid compositions of the present invention can make ageneral improvement to the flavour of foods or beverages. The reactionflavour solid compositions may be added to a food or beverage by simplemixing with other ingredients in the final blending of a food orbeverage, such as a convenience food. Alternatively, the reactionflavour solid composition may be added to the outside of a food orbeverage, for example, the process of dusting or spray coating a snackfood. Still further, the reaction flavour solid composition may be addedto a food or beverage during its formation, in a process which issometimes referred to as internal flavouring.

The reaction flavour solid compositions of the present invention arewell-suited for use, without limitation, in the following products:

Confectioneries, preferably selected from the group consisting ofchocolate, chocolate bar products, other products in bar form, fruitgums, hard and soft caramels and chewing gum;

Baked products, preferably selected from the group consisting of bread,dry biscuits, cakes and other cookies;

Snack foods, preferably selected from the group consisting of baked orfried potato chips or potato dough products, bread dough products andcorn or peanut-based extrudates;

Cereal products preferably selected from the group consisting ofbreakfast cereals, muesli bars and precooked finished rice products;

Alcoholic and non-alcoholic beverages, preferably selected from thegroup consisting of coffee, tea, wine, beverages containing wine, beer,beverages containing beer, liqueurs, schnapps, brandies, sodascontaining fruit, isotonic beverages, soft drinks, nectars, fruit andvegetable juices and fruit or vegetable preparations; instant beverages,preferably selected from the group consisting of instant cocoabeverages, instant tea beverages and instant coffee beverages;

Spice blends and consumer prepared foods, including powder gravy, saucemixes, condiments and fermented products;

Ready-to-heat foods: ready meals and soups, preferably selected from thegroup consisting of powdered soups, instant soups, precooked soups;

Dairy products milk products, preferably selected from the groupconsisting of milk beverages, ice milk, yogurt, kefir, cream cheese,soft cheese, hard cheese, powdered milk, whey, butter, buttermilk andpartially or fully hydrolyzed milk protein-containing products Flavoredmilk beverages;

Soya protein or other soybean fractions, preferably selected from thegroup consisting of soya milk and products produced therefrom, soyalecithin-containing preparations, fermented products such as tofu ortempeh or products produced therefrom and soy sauces;

Meat products, preferably selected from the group consisting of ham,fresh or raw sausage preparations, and seasoned or marinated fresh orsalt meat products;

Eggs or egg products, preferably selected from the group consisting ofdried egg, egg white and egg yolk and oil-based products or emulsionsthereof, preferably selected from the group consisting of mayonnaise,remoulade, dressings and seasoning preparations; and

Fruit preparations, preferably selected from the group consisting ofjams, sorbets, fruit sauces and fruit fillings; vegetable preparations,preferably selected from the group consisting of ketchup, sauces, driedvegetables, deep-frozen vegetables, precooked vegetables, vegetables invinegar and preserved vegetables.

The invention is described in greater detail by the followingnon-limiting examples.

EXAMPLE 1

A mixture (Sample 1) was prepared and processed following the procedurebelow:

To 165 g water in a glass beaker, a protein source (220 g), amino acids(33 g), a reducing carbohydrate source (55 g), caustic (16.5 g, 1 N) andbeef fat (60.5 g) were added under vigorous stirring to the point wherea homogenous suspension formed. The free flowing slurry was then pouredin a crystallisation dish and submitted to microwave irradiation (e.g.600 W, 7 minutes, 2450 MHz. atmospheric pressure). Shortly afterswitching on the microwave the water started to boil and frothing wasobserved. After evaporation of the water fraction the temperatureincreased further. Upon reaching the peak temperature of 145° C.microwave power was switched off. The glassy material was allowed tocool to ambient temperature. The solidified material (1-3% moisture) wascoarsely crushed before fine milling to 300-2000 μm.

Preparation of a Comparative Sample Using a Conventional Batch Reactor

The materials mentioned above in the preparation of Sample 1 wereprocessed in a closed, conventional, double-jacketed glass reactor(volume of 1 litre) equipped with an anchor stirrer and temperaturesensor. After establishing a suspension of the starting materials at 50°C., the slurry was heated to 115° C. within 70 minutes. After reaching115° C., the slurry was kept at this temperature for 65 minutes(pressure build up was observed: 1.5 bar). After the reaction the batchwas cooled down to 50° C. again within 40 minutes. The resulting liquidwas blended with an amount of carrier and was subsequently spray driedon a Niro Minor type spray tower.

Evaluation of Sample 1 and Comparative Sample

Sample 1 was evaluated by trained panellists alongside a comparativesample containing identical ingredients but which was prepared in aconventional batch reactor with anchor stirrer followed by subsequentspray drying of the reaction slurry. Results of the evaluation areprovided below:

The Sample 1 was determined to be approximately twice the strength ofthe comparative sample. Furthermore, it was considered to have a moreintense and complex flavour that was more reminiscent of flavoursobtained by cooking techniques. By comparison, the comparative samplewas deemed to be less authentic

EXAMPLE 2

A mixture (Sample 2) was prepared and processed following the procedurebelow:

In a preparation tank 472 g drinking water was mixed with 400 g of ayeast extract, 70 g vegetable oil and 15 g amino acids. After forming ahomogenous slurry, 25 g were poured onto a crystallisation dish (3-5 mmlayer thickness). The slurry was microwave treated at 800 W for 6minutes at atmospheric pressure. First frothing of the slurry wasobserved immediately after reaching boiling temperature of water andafter evaporation of the water fraction, the reaction foamed a secondtime and ultimately solidified (Maximum temperature at the point powerwas switched off: surface temperature was 148° C. (IR), 161° C. inside(Pt 100 standard resistance thermometer). The final water content of thesample was 1.5-2.5 wt %. After cooling for 4 minutes, the resultingbrittle product was ground with a mortar and pestle. The resultingpowder particle size was 300-2000 μm. The resulting powder was stableand free flowing over a test period of 6 months at ambient temperature.

A comparative product was prepared in a batch reactor using thematerials employed in the preparation of Sample 2. The materialsmentioned above were processed in a closed, conventional,double-jacketed glass reactor (volume of 1 litre) equipped with ananchor stirrer and temperature sensor. After establishing a suspensionof the starting materials at 50° C., the slurry was degassed to preventexcessive foaming during reaction. Then the slurry was heated to 105° C.over a period of 55 minutes. After reaching 105° C. the slurry was keptat this temperature for 135 minutes (pressure build up was observed: 0.6bar). After the reaction the batch was cooled down to 50° C. again overa period of 35 minutes. The resulting liquid was blended with a carrierand was subsequently spray dried on a Niro Minor type spray tower.

Sample 2 was evaluated by trained panellists alongside the comparativesample containing identical ingredients but which was prepared in aconventional batch reactor with anchor stirrer followed by subsequentspray drying of the reaction slurry. Results of the evaluation areprovided below:

Sample 2 provided a novel and complex character with strong roasted andpronounced animal species specific attributes, whereas in thecomparative product yeast character dominated. Sample 2 was consideredto provide a more authentic flavour reminiscent of flavours obtained byconventional cooking techniques, whereas the comparative sample bycontrast was considered to be less authentic.

EXAMPLE 3

In an adequate preparation tank, a suspension of 41 g fruit syrup, 19 gL-proline (0.17 mol), and 15 g Na-citrate (0.06 mol) were prepared.After adding 27 g maltodextrin, the obtained slurry was subjected tomicrowave processing (2 minutes at 800 W followed by 3 minutes at 300W). Significant foaming was observed. Maximum temperature was measuredby IR as 111° C. While cooling, the hot, viscous mass solidified. A dry,foamed, brittle material was obtained, which was milled (Retsch ZM100,Germany) under controlled atmosphere. The water content measured as 2.3%(Moisture Analyser HB43, Mettler-Toledo, Switzerland).

Functional organoleptic comparison of the microwave processed productwith a conventionally, water based, batch processed alternative (spraydried after processing) allowed a 7-fold dosage reduction of themicrowave processed product to provide equal functional performance in abouillon type tasting base.

1. A process of preparing a reaction flavour solid compositioncomprising the step of heating an aqueous slurry containing reactionflavour precursor compounds using microwave radiation to form a reactionflavour and concomitantly drying the slurry to form a reaction flavoursolid composition.
 2. The process of preparing a reaction flavour solidcomposition according to claim 1, wherein the water content of theaqueous slurry is 15-50 wt % of the total weight of the slurry.
 3. Theprocess according to claim 1, wherein the water content of the reactionflavour solid composition is 0.5 to 5 wt % based on the total weight ofthe reaction flavour solid composition.
 4. The process according toclaim 1 wherein the slurry is heated for a period of time ranging from 1to 15 minutes.
 5. The process according to claim 4, wherein the slurrymay be heated to a temperature up to 180° C.
 6. The process according toclaim 4, wherein the slurry is heated to about 100° C. for a period oftime to evaporate off most of the water, before heating the slurry to atemperature selected from the group consisting of a temperature of up to125° C., 130° C., 140° C., 150° C., 160° C. or 180 C.
 7. The processaccording to claim 6, wherein the slurry is heated to a temperature ofabout 100° C. for a period of 1 to 5 minutes.
 8. The process accordingto claim 1, wherein the slurry is heated at ambient pressure or under avacuum.
 9. The process according to claim 1, wherein the slurry is inthe form of a film having a thickness between 0.3 and 5.0 cm.
 10. Theprocess according to claim 1, wherein the slurry has a viscosity of1′000 to 50′000 centipoise at room temperature.
 11. The processaccording to claim 1, wherein the slurry is free of carrier materials.12. A reaction flavour solid composition prepared by the process ofclaim
 1. 13. A food or beverage comprising the reaction flavour solidcomposition of claim
 12. 14. A method of imparting flavour to a food orbeverage, or of modifying or improving the flavour of a food orbeverage, said method comprising the step of adding to said food orbeverage the reaction flavour solid composition of claim
 12. 15. Theprocess according to claim 2, wherein the water content of the reactionflavour solid composition is 0.5 to 5 wt % based on the total weight ofthe reaction flavour solid composition.
 16. The process according toclaim 1, wherein the slurry is heated for a period of time ranging from1 to 10 minutes.
 17. The process according to claim 1, wherein theslurry is heated for a period of time ranging from 1 to 5 minutes. 18.The process according to claim 5, wherein the slurry is heated to about100° C. for a period of time to evaporate off most of the water, beforeheating the slurry to a temperature selected from the group consistingof a temperature of up to 125° C., 130° C., 140° C., 150° C., 160° C. or180 C.